vl/compositor: fix weave shader bugs

Writemask was XY instead of YZ (thanks to calim for spotting it).

The pixel calculation resulted in the pixel always being off by one.
If y was .5:

y' = round(y) + 0.5 = 1.5

Fixing this also means the LRP function has to swap the pixels it, since
it's now the other way around for top/bottom.

WIth these fixes only chroma for top and bottom pixel rows are wrongly interpolated
in my test program:

--- nvidia
+++ nouveau
@@ -1,4 +1,4 @@
-YCbCr[0] = 00c080
+YCbCr[0] = 00b070
 YCbCr[1] = 00b070
 YCbCr[2] = 029050
 YCbCr[3] = 207050
@@ -61,4 +61,4 @@
 YCbCr[60] = 0c5070
 YCbCr[61] = c05090
 YCbCr[62] = 0e70b0
-YCbCr[63] = e080c0
+YCbCr[63] = e070b0

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
vl/video_buffer: fix up surface ordering for the interlaced case

It seems the other code expects surface[0..1] to be the luma field in interlaced case.

See for example vdpau/surface.c vlVdpVideoSurfaceClear and vlVdpVideoSurfacePutBitsYCbCr.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
nvc0: Add support for video buffer
Fix mapi code generator for out-of-tree build

Use os.path.join() rather than hand-rolling it, so path is correct if
sys.argv[0] returns an absolute path.

(According to the python documentation, it's platform dependent whether
sys.argv[0] is a full pathname or not.  It probably also depends on how
the process was started...)

Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
build: Make src/gtest before src/mesa

Fixes a make check problem where libgtest.la wasn't build before tests
that want to link with it.
WIP: get rid of in/out ambiguity

Note: I eliminated all the places where we were trying to allow shader
inouts.  These aren't allowed, and our grammar rejects them, so they
should never occur.
WIP: allow varying structs
Partial varying struct support.  TODO: disentangle and comment better.
Disable structure splitting for "in" and "out" vars.
Got the initial varying struct test to pass